Iam using jDeveloper for developing my application which is connected to a postgresql database. To use diffrent tables in my Application I connected them by a EJB Diagram. After that I created a session bean in that Diagram.

To use that Data in my Application I create a new Data Control for that Session bean.

After moving the Data Control to a Table in my index.jsf I run my programm and get this error:

+Exception Description: The type [class java.lang.Object] for the attribute [id] on the entity class [class model.StundenzettelEintraege] is not a valid type for a serialized mapping. The attribute type must implement the Serializable interface.+

The Problem is that the jDeveloper maps diffrent number types (in postgre for example serial, int,..) to the java.lang.Object class.
Where can I configure that behavior to solve this problem?